Theoretical Study of the Performance and Efficiency Droop of a ZnO‐Based Multiquantum Well Light‐Emitting Diode

A zinc oxide‐based multiquantum well light‐emitting diode is proposed in this paper. MgZnO is used as the barrier, and CdZnO compound is used as the quantum well. Due to difficulties toward synthesis of p‐ZnO, a p‐GaN layer is used as the top layer. Also, a p‐MgZnO layer is utilized as electron‐blocking layer. The performance and efficiency droop (ED) of the modeled device then are studied with different Mg and Cd concentration, thickness of quantum barrier, number of quantum well, and carrier concentration of p‐GaN layer. During an optimization operation, the optimized values of these parameters are determined. It is revealed that the carrier concentration of p‐GaN layer is the most influencing parameter on the quantum efficiency and ED of the modeled device. A multiquantum well (MQW) light‐emitting diode (LED) design including p‐GaN/p‐AlGaN/Mg x Zn1−x O/Cd y Zn1−y O/n‐Mg x Zn1−x O/n‐ZnO structure is proposed in this paper. Herein, some solutions regarding the possible challenges toward the development of ZnO‐based MQW LEDs are seeked. Particularly, the efficiency droop of these devices is studied fundamentally.